Method and apparatus for distilling oil



July 29, 1930. J. c. BLACK METHOD AND APPARATUS FOR DISTlLLING OIL FiledOG.. 26.- 1925 .Ill

Patented July it. 1523@ l I i UNITED STATES PATENT OFFICE JOHN BLACK, FDESTREHAN, LOUISIANA .s

METHOD AND APPARATUS FOR DISTILLING OIL Application led October 28, 192mSerial No. 144,345.

This invention is directed to aprocess, and pump 3 through lines 2 and4, by the correct an apparatusfor the distillation of liquids,manipulation of valves 4 and 41' through particularly liquids of thenature of oil. analyzer The amount of oil passing An object of thisinvention is the better through thls analyzer 1s regulated by the reg- 5utiiizotion of hoot and for an improvement in ulation of theaforementioned valves, in order 55 the practical Operation ofdistiiiotion oquip to control the ref lux action 1n bubble tower mentfor carrying out this process.' 25. The oil passing from analyzer 5passes,

The invention will be better understood by tieglhrlltglggis?)ofihglgill; reference to the accom an ing drawing which shows aschematic rraligement of an picked u Considerable heat by means of thmo0 a t t s fo t th b invelb heat exc ange, and has had lts vaporprestizmai'ngu e a' Ove sure so 'augmented that when it is run into 1'is a tank contaiing the material to be img-1 juugiu 11 perftayts 13ull-? eisie w1 eaio uveryi i5- ogalsvglilldb o2) 152% n; steam. Xaplrriintgbiln still 121 is clfaned of 05 entraine oi in u e tra s 5 anpasses annata? fissati-integraal; @with uit 16;@ ioinwitigh@ 25. 4 isvalve in said line. 6 and 7 are lines mg rou co umn 2 unvaponze portiono the oil is then pum ed by pump oo (slmrcglsn lizl satlinlatoeshsl; 17through coil 18. In coil 18 irt is heated to th d ired tern rat r furnac19. The connectmg heat @Xchallger 8 WPh heat heites oil thenpgasselsetllirilough lixe 20 into exchanger 10. 11 1s a line connecting heatexchanger 10 with stripping still orA evapgie .eiapfar .21 o?? trays 2.23711116 it i orator 12. 13 are trays in said still. 14 is Ism ed y meanso lts coutume eat an b th id of a little steam.y It is cleaned in 75 25y e a 9', Steam 6.011 in Sad. Shu' 15 .are bubble trays 24 of anyentraned oil, and rises @rays in Smd $511.1' 16 1S a vapor Ime qonnet'through trays 27 in bubble tower 25 where it mg 111.12 with bubble tower25. 17 1S a hn? is fractionated by the aid of reflux generatedv onpectmgstm i2 wltll 0011 .18 Vla. Pump 17 by analyzer 5. Condensate formed inthis 19 is a furnace 1n which coil 18 is situated. bubble tower istrapped out in tmp 26 and 20 is a cross-over line connecting coil 18with removed througi1 lino 28 hoot eXohiiiigoi. 8 ova-Potatoo 21- 22alo'oys 1,11 Sold ovo'Po' to tank 30. Unvaporized oil collecting inrator. 23 1s asteamcoil 1 n said evaporator. evaporator Q1 is passodthrough lino 31, 24 are bubble trays 1.o Sad evaporator' 26 throughexchanger 10, through line 32 via 1s a condensate trap in bubble tower25. pump 33 to storage in 34 Vapor I.ising from 85 are bubble trays insaid bubble tower. 28 1s the top of tower 25 through lino 35 is conacondensato rundown Ime ffom trap 26 densed in condenser 36 andsent'through lookthrough heat exchanger 8 and line 29 to storbox 37 inline 39 to Storage in tank 40. Um

age tank 30. 31 is aresidue line connecting y nt d th h o evaporator 21with heat exchanger 10. 32 lg'ggfi vapors are ve e mug vapor oo 1s a huecomlectmg heal exchanger 10 wth By the above method considerable heat istank 34.' .33 1S a pllmp m Sala Ime 35 15a abstracted from the hot oilissuing from the vapor line connecting bubble tower--w1th evaporator 21and from tow-er 25. The oil so condenser 36. 37 is a lookbox incondenser 45 line which connects condenser 36 via line 39V hoaod hasConsiderable Vapor Pross1ro and 05 with tank 40. 38 is a va or ventconnected great dloolty 1S foon@ 1H Pomlng this o1 te lookbox 37, 41 isa' ypas$ connecting to and through the coil. T he lines become line 4with line 7. 41 is a valve in said line. Vapor-bound and the operationof the pump The operation of this system is as follows: may he almostentirelyiimpossibla In order so Crude oil contained in tank 1 is pumpedby to avoid this difficulty and yet obtain the de- 100 the ligbhgtvolatile vsirable heat eiciency resultin from the heat exchange inexchangers 8 an 10, I separate products from this preheated oil foresendlng it to the pump and heating coils. This stripped oil is theneasily pumped.

both. It is an expensive process to remove these undesirable contituents. It is well known in the art that the lower the temperature towhich the oil is heated before vaporization, the less dotheseundesirable constituents form.

In thje usual processes of fractionating,

the oil'mustbe sufficiently heated during the passage through heatercoils to cause 1t to evaporate land the [vapors'must carry sui- L cientyheat on `their passage through the fractionatingtower to keep thedesired fractions from condensing during their relatively long `periodof passage up the fractionating tower and over to the condenser box.

u By this process `I can heat the oil to a lower temperature duringjthepassage through the heating coil,and, consequently, the above mentionedundesirable constituents are formed in a lesser amount. This object 1sachleved by using the lighter fractions of the desired finishedgasoline, whichcome from the stripping still, asa carrier in the bubbletower for the heavier fractions of the desired finished Y gasoline byinjecting the vapors of the ghter vfraction ata relatively high point inthe fractioning tower, thus doing away with some of the steam heatnecessar to carry over the"` vapors of the heavier fractlons, and so, asbefore stated, being' able to distill at a lower temperature. l

,\A`s a specific example of the operation of this system the followingmay be recited. Crude oil is passed through the analyzer 5 and 'is thereraised to\ a temperature of about .200 F. It" then passes through heatexchangers 8 and 10 where it is raised an additional amount,approximating 100 F., and is evaporated in still 12. Only a very smallamount of steam is added, just sufficient to act as a. carrier for thevapors. The amount of crude gasoline vapors distilled out of the crudeoil amounts from 8% to 10%'of the crude. The residual oil issuing fromthe still through line 17 has been partlally cooled by this evaporationso that it issues through line 17 at about 200 F. It is stripped of alllight, volatile fractions, and is therefore easily pumped by pump 17through coils 18 and is raised to about 550 F. or 600 F. It isevaporated in an evaporator 21 by aid of some steam introduced throughcoils 23, to form a fuel oil fraction consisting of about 60% and thenthrough an additional cooler, if desired, to storage in tank 30. Theoverhead vapors which consist of about 20% to 25% of the crude oil, iscrude gasoline, and this is condensed in condenser 36 and collected intank 40.

As will be observed, a considerable proportion cf li ht volatilehydrocarbon vapors is obtained y the heat picked up in heat exchangers.vThese vaporous products interfere with the operation of the pump as regviously described. By removing them be ore passing the oil tothe. pump,the operation is greatly facilitatedand is cheapened, since thisdistillation of light hydrocarbons is obtained gratis, the heat havinbeen expended in heater 18 for the distillation of the main lbody ofoil.

The above is not to be taken as limiting my invention, but merely asillustrative of the best manner of carrying out my invention which Iclaim to be:

1. A continuous process of distilling hydrocarbons which comprises,passing the hydrocarbons to be distilled in heat exchange with residualvapors, a condensate and an unvaporized fraction of the subsequentdistillation; vaporizing and fractionating the thus preheatedhydrocarbons in a fractionating tower to separate the lower boilingfractions present 1n said preheated hydrocarbons, passing the higherboiling hydrocarbons, substantially free of the lower boilinghydrocarbons, to and through a heated coil to heat said hydrocarbons;vaporizing a part of the heated hydrocarbons to form an unvaporizedfraction; fractionating the vapors thus formed to form the abovementioned condensate and residual vapor, injecting the aforementionedlower boillng hydrocarbons into the last fractionating unit, so `thatthe lower boiling hydrocarbons lower4 the vapor pressure of the heavierfractions from the last mentioned fractionation and assist in thevaporization of said heavier fractions. v

2. A continuous process of distilling hydrocarbons which comprises,passing hydrocarbons to and through a heated coil to heat saidhydrocarbons; vaporizing a part of the heated hydrocarbons;fractionating the vapors thus formed to give a condensate and residualvapor; passing the residual vapors, the condensate and the unvaporizedfraction in heat exchange with hydrocarbons passing to the heating step;vaporizing a part of the thus pre-heated hydrocarbons to separate thelower boiling fraction ypresent in said preheated hydrocarbons andinjecting said lower boiling fraction into the upper part of thefractionating unit of the first mentioned fractionating step, so thatthe lower boiling fractions act as a carrier for the heavier fraction inthe first mentioned fractionating step, and conducting the unvaporizedfraction from a distillation tower em loyed to se arate the low boilingfractions rom the pre eated hydrocarbons to and through said firstmentionedv coil.

3. An apparatus for distilling hydrocarbons which comprises, a coilsituated in a furnace; an evaporator; means for passing hydrocarbonsfrom said coil to said evaporator; a fractionating device connected tosaid evaporator; an analyzer; means for passing vapors from saidractionating device through said analyzer; means for withdrawing thevapors from said analyzer; means for withdrawing condensate from saidfractionating device "means for withdrawing the unvaporized fractionfrom said evaporator; means for passing hydrocarbons through saidanalyzer in heat exchange with said vapors; and means for passing thelast mentioned hydrocarbons in heat exchange relationship with thecondensate from said fractionating device and with the unvaporizedfraction from said e Japorator a second evaporator; means for passingthe incoming preheated hydrocarbons from said heat eX- changers to saidsecond evaporator; a pipe connecting said second evaporatorto 4saidfurnace heated coil and a pump in said line;

a second fractionating device connected to said second evaporator; meansfor passing vapors from this fractionating device to the up er sectionof the first fractionating device. n testimony whereof I aix mysignature. JOHN C. BLAKr

